In typical conventional walking shoes, the wearer's heels are elevated above the wearer's toes and the balls of the wearer's feet when the wearer is standing. In some slippers, the heels, toes and balls of the feet of the wearer are coplanar. In a few prior art instances, shoes have been provided with reverse wedges (i.e., ones which are taller in front and taper rearwardly), but so far as the present inventor is aware, in each of the latter instances, the reverse wedge has extended under the wearer's heel, and/or the reverse wedge has been provided on the outside of the bottom of the sole as a rather obvious addition. In some instances, the reverse wedges have been applied to rigid soles, or have caused the soles to which they were added to become rigid soles. These features have, in the estimation of the present inventor, limited the amount of exercise that a reverse wedge can provide to a shoe and/or limited the potential market for reverse wedge exercise-enhancing shoes.